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Chapter 15 Birds and Mammals
animal that eats only other animals or the remains of animals
strong, lightweight feathers that give their birds their coloring and shape and that are used for flight
soft, fluffy feathers that provide an insulating layer next to the skin of adult birds and that cover the body of younger birds
vertebrate animal with a constant internal temperature
period of which an embryo develops in the uterus
animal that eats only plants or parts of plants
endothermic vertebrates that have hair, teeth specialized for eating certain foods, and whose females have mammary glands
milk producing glands of female mammals used to feed their young
a mammal with an external pouch for the development of its young
mammals that lay eggs with leathery shells
animal that eats both plants and animals
sac-like organ in which a placental embryo develops
a mammal whose offspring develops in a female uterus
when a bird rubs oil from an oil gland to its wings to condition them
connects the embryo to the placenta moves food and oxygen to the embryo and then removes its wastes